V6

Reflectometer

Instrument description

The reflectometer V6 allows measuring the neutron optical reflectivities on flat surfaces at grazing angles. The reflectivity is related to the variation of the refractive index within a depth of about 200 nm, thus structural depth profiles can be studied at solid-air, solid-liquid and free liquid surfaces.

For solid samples the angle of incidence is varied by a precise tilting of the sample surface relative to the (fixed) collimated neutron beam. Liquid samples can also be measured. In this mode the sample surface is kept horizontal and the angle of incidence is varied by precise and synchronized movement of the monochromator tilt angle, the slit system and the sample stage.
The sample-detector distance is variable between 1m and 3m.

Applications

  • Multilayers (inorganic or organic materials)
  • Liquid and solid surfaces, solid-liquid interfaces
  • Properties of in-plane structured layers

Selected examples

a) Polymer-Induced Swelling of Solid-Supported Lipid Membranes

b) Probing adsorption and aggregation of insulin at a poly(acrylic acid) brush

c) Influence of Binary Polymer Mixtures on the Nonlinear Growth Regimes of Polyelectrolyte Multilayer Films



List of publications
Instrument Data
Neutron guide NL 4
Collimation 2 Cd slits (computer controlled)
Monochromator PG (002)
mosaicity: Δλ/λ = 2%
Wave length λ = 0.466 nm
Wave length resolution
Scattering plane vertical
Flux 3·104 n/cm2s
1.5·104 n/cm2s (polarized 98.5%)
Range of reflectivities 2·105 (with sample site 10x40 mm)
q resolution 2·10-2 nm-1 (depending on collimation)
Detector 48 3He-detector tubes
optionally multiwire PSD (180 x 180 mm, resolution 1.5 mm)
Angular range: 10° (for liquids: 0° - 2.7°)
Vertical collimation: 0.01° - 0.05°
Angular precision: 0.001°
Maximum sample size
Polarized neutrons no
Guide field
Instrument options • solid sample mode
• liquid sample mode
Sample environment • sample rotation table (360°)
• heatable sample cells for air-liquid and solid-liquid interfaces
• high pressure cell (100MPa) for solid-liquid interfaces
• vacuum and gas loading cells
• Langmuir film balance
Software